WE TA 2015, P90 review

[renegadecow]

Could it be varying bb seat depth?

[DarkLite]

NEEEEEEEEEECRO

Got one of these in for a few fixes, got everything sorted bar two issues:

1) The internal gas tank will vent out of the top when you change magazines

2) One of the magazines is leaking out of the outlet valve and nothing I've tried so far has fixed it

Does anyone have any ideas?

[renegadecow]

1) The coupling valve (gun end) isn't seating well (probably from being mashed). Take the valve out and lightly ream the hole it sits in to give it more wiggle room.

2) The coupling valve (mag end) and its o-ring has very tight tolerances sitting in its brass sub assembly and if it shrinks just a little you get that persistent hiss. What I've found to be a surefire solution is building up the diameter of the recess for the o-ring with super glue. I put enough glue so that the lower meniscus (while still wet) is around 1/3 the depth of the pocket. I apply the glue while it's vertical in the chuck of a drill and slowly spin it for the glue to even itself out. The hard part is removing it from the chuck without disturbing the  glue or you could keep it propped up in the drill until it cures.

[DarkLite]

9 hours ago, renegadecow said:

1) The coupling valve (gun end) isn't seating well (probably from being mashed). Take the valve out and lightly ream the hole it sits in to give it more wiggle room.

2) The coupling valve (mag end) and its o-ring has very tight tolerances sitting in its brass sub assembly and if it shrinks just a little you get that persistent hiss. What I've found to be a surefire solution is building up the diameter of the recess for the o-ring with super glue. I put enough glue so that the lower meniscus (while still wet) is around 1/3 the depth of the pocket. I apply the glue while it's vertical in the chuck of a drill and slowly spin it for the glue to even itself out. The hard part is removing it from the chuck without disturbing the  glue or you could keep it propped up in the drill until it cures.

You legend. Absolutely spot on with both fixes.

[Zereck]

I noticed that mine has slower rof and less kick even with new nozzle. When I do the nozzle check I can feel the resistance but also the air going out at the pin holding the nozzle spring. Could that be the problem? I don't have any leak otherwise.

[Zereck]

I know I'm asking a lot here but I have a weird problem. The gun works fine if I'm shooting it empty but if use a loaded magazine the gun goes like this:

1. shots bb, weak recoil - 2. no bb, strong recoil - 3. shots bb, weak recoil - 4. no bb, strong recoil, etc. 

I checked if there is any misalignment but I couldn't find any. Tried different BBs and when I used lighter ones the recoil was still weak but it feed constantly at least.

Curiously I put one BB in the chamber and shot it without magazine and it gave me the same weak recoil.

[renegadecow]

Sounds like your floating valve is getting stuck

[Zereck]

Sorry for the late update. I have tried multiple floating valves and spring and it would keep doing the same thing so I bought a new bolt. With it the gun finally shoots normal there are differences in the look but I think the fault was that the pin that holds the nozzle in the bolt became somewhat loose(and the hole it goes into) after hammering it in and out a lot.

Similar thing happened in my WE MP7 which was showing syptoms of very fast cooldown. The bolt was leaking at the nozzle holding pin hole(even tough the pin is all the way in). Just a thing to watch out for if you take the gun apart a lot.

[LJ.NL]

Playing around with my P90 to see if I can get it to run nicely for CQB, I'm wondering if it's possible to disable full-auto?

Looking at the sears I'm thinking of grinding some material off part number 17: the spot thats in contact with part number 24 (that's also beeing smoothed for a lighter trigger pull). If I remove just enough material, so that nr 17 doesn't get pushed far enough for full-auto, I can put the fire selector on full-auto and it'll just fire one shot, right? Or am I looking at things wrong?

Thanks!

[renegadecow]

That won't work. #17 is the semi auto sear and is pushed back far enough to clear the hammer in semi and full. What happens in full auto is #20 disconnector is also pushed back so it won't catch the hammer. Removing the protrusion on #24 that pushes #20 will keep it firing in semi-auto no matter how deeply you pull the trigger. But it would be easier to just add material to the selector so that semi and full limits trigger pull to the same distance and is easily reversed.

[LJ.NL]

Thank you for clearing that up!

I've tried adding material to the selector and triggerbar places, but I still get 2 or 3 shot burst on semi (sometimes 1 shot, but mostly short bursts).

I've checked the trigger parts and part #25 is bent a little bit (but not as much as other users have shown in this topic), could that be the issue?

Also; I'm running it on hpa, and it cycles pretty fast, maybe to fast to engage the sears after just on shot?

Thanks again!

[renegadecow]

There's the possibility that the sear or disconnector is beginning to conk out. I remember mine doing that until I eventually replaced it with a steel set. 

Edited April 29, 2019 by renegadecow

[LJ.NL]

Yes, I figured it's best to go for a steel set also, and go from there. As it seems the 'sweet spot' for semi or full-auto/burst is getting smaller every round fired

Thanks again for the help, I'll update once I have things sorted!

(I'm building a backpack-bb-feeder thingy into the magazine to avoid having to build high-caps or dragging around multiple expensive/heavy mags. If it works I'll share it here.)

[LJ.NL]

Allright, installed the steel trigger parts: works like a charm! Way better trigger pull and no more burst issues on semi. Looking back I think my trigger was buggy from day one, as this is much much better.

Newly created problem while testing: the nozzle broke.. One side/wing of part #109 gave out, making pin #117 slide out a bit, tearing out the pin-holes on #109 and #110. Have to replace the nozzle or maybe try a fix with new drilled holes and glue it together.

[Zereck]

I played with it last weekend and it worked nicely except for one thing. 2 times that day after a magazine change my shots resulted ib gas clouds exiting at the end of the barrel and lost hop-up. At that point magazine change didn't fix it I had to readjust the hop, like I have lost FPS but it wasn't really cold(15 celsius). Weird.

My ROF is still slow most of the time but sometimes it gets quicker? I noticed this after a bigger maintenance:

https://imgur.com/a/IGSAXHS

The auto-sear(?) was hitting the gas tank. Did this only happen to me?

[Zereck]

I don't know if anyone still lurks here, but remember how I had the issue with weaker recoil and low rof? Well it's gotten worse and I think I know the issue but not how to fix it.

I have over time checked everthing on the gun nozzle, bolt, trigger assembly, innert gas tank. No leaks or anything broken.

However I did notice that the inner tank barely holds any gas. If I shot the gun without magazine I could only get a few shots. Then I could get only one and the other was just psssh. Now even the one is weak. It's like gas doesn't flow inside the inner tank and causes rapid shots or full auto to  simply end in suped quick cooldowns. In a few shots tha gun just spews out the gas. This happens with all my magazines so I checked the inner chamber for any damage but aside the pne on the outside mentioned in my previous post I found nothing. I tried removing the gas inlet valve so that gas could flow in from the mag directly but still had the same performance. Lastly I just bought a new inner tank. Nothing changed. I am using propane, tough I used it from the beginning so it shouldn't be the issue.

[Zereck]

On 3/16/2020 at 9:38 PM, Zereck said:

I don't know if anyone still lurks here, but remember how I had the issue with weaker recoil and low rof? Well it's gotten worse and I think I know the issue but not how to fix it.

I have over time checked everthing on the gun nozzle, bolt, trigger assembly, innert gas tank. No leaks or anything broken.

However I did notice that the inner tank barely holds any gas. If I shot the gun without magazine I could only get a few shots. Then I could get only one and the other was just psssh. Now even the one is weak. It's like gas doesn't flow inside the inner tank and causes rapid shots or full auto to  simply end in suped quick cooldowns. In a few shots tha gun just spews out the gas. This happens with all my magazines so I checked the inner chamber for any damage but aside the pne on the outside mentioned in my previous post I found nothing. I tried removing the gas inlet valve so that gas could flow in from the mag directly but still had the same performance. Lastly I just bought a new inner tank. Nothing changed. I am using propane, tough I used it from the beginning so it shouldn't be the issue.

Forgot to update but I found the issue and it was my fault.  I misjudged how the gas release valve works on the magazine. I put a small teflon where the o-ring is and then put the rubber on thinking it would help sealing. Well it did in a way it restricted the gas flow to a point it made the gun unable to shoot and since I did it on most of my magazines I didn't think about it at first. Oh well.

Also we found out that the propane we bought was something else as even Marui guns had cooldown issues by now. It's annoying that I didn't think about it sooner I needlesly tried to repair my WE MP7 when the only problem was the gas. Bah.

[HmmBen]

Hi guys. I have very recently bought one of these to fulfill my p90 urge and this thread has been amazing.

Has anyone done anything about the slack between the upper and lower receiver?

I made two rubber blocks to sit each side of the hop unit which has improved this no end however I am yet to test this in the field.




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[Aemeneol]

Hey there, I just got one of these recently and I've been loving it so far, almost at the 1000 round count just from testing things out. In that time I've done mods to my only mag to remove leaking, and I've tried to check if using some O-rings to keep the stock bolt stop in place would help its longevity. I mean it probably did, I think it lasted maybe a few dozen stops, but ultimately broke. 

I tried to make a bolt stop out of polycarbonate to practice making one out of nylon, but I don't think I have the hand dexterity for it. I was thinking of other ways to help the bolt stop, since I think my next course of action would be to order a stock one again from KYAirsoft.

I was thinking of getting the YSC Aluminum Bolt Carrier, since it's lighter, and given a few more mods might help with the longevity of the stop even further. But I guess my question would be has anyone actually tried that thing out? I'm not sure of its quality. I'm currently content with running it without a bolt stop, but it's something I'll probably mess around with in the future if the part is at least of good quality.

So my second issue is, I recently switched out my inner barrel to an aftermarket 250mm barrel so I could use my Maple Leaf MR.Hop (I've used this on my other guns so I just like this setup at this point). It works flawlessly on semi-auto, but I'm having a bit of trouble with Full-Auto bursts (I've only tested 3~4 round bursts, eventually when I move on to the Z-Parts trigger set I'll probably *rickroll* around with full auto more). Sometimes all 3~4 shots shoot no problem, other times, it just kind of chucks one shot a few feet away. It does this with both the new (250mm) barrel and the stock (270~ish mm). I was thinking the BBs might be hitting the 'outer barrel' on the way out of the gun. I was wondering if this happens to anyone else, and if a longer barrel (maybe stopping short of the end of the threads) fixed it, or if this is really just how full auto/bursts work on GBBRs. I have a WE 416 that I can full auto with, but that inner barrel ends right as the flash hider begins so nothing really gets in the way, so that thing's full auto doesn't hiccup.

Any input would be appreciated, thanks!

[Aemeneol]

False alarm on the full auto issue, I just put back the nub that prevents double-feeding back wrong and that caused issues. 

My dilemma regarding the bolt stop continues.

[Zereck]

Funny thing is my first bolt stop broke in a month or so. I bought 2 WiiTech ones then and they couldn't last a few tries. I started modelling one and bought 2 WE ones until I was done. But first one lasted at least 2 years and I only installed 2nd one a few months ago. So I tought WE fixed or at least made the bolt stop stronger.

[Aemeneol]

I'm trying to figure out how to reduce the wiggle room the bolt stop has, because that's primarily what's causing the break, the forces applied on it aren't equal so one section of the bolt stop eventually just 'folds' and breaks.